(function (doc,win){
  var doEl=doc.documentElement,
    reseizeEvt = 'orientationchange' in window ? 'orientationchange':'resize',
    recalc=function (){
    var clientWidth=doEl.clientWidth;
    if(!clientWidth) return;
    if(clientWidth>=750){
      doEl.style.fontSize='100px'
    }else{
      doEl.style.fontSize=100*(clientWidth/750)+'px';
    }
    };
  if(!doc.addEventListener) return;
  win.addEventListener(reseizeEvt,recalc,false);
  doc.addEventListener('DOMContentLoaded',recalc,false);
})(document,window);
